specgen: honor userns=auto from containers.conf

when using the default userns value, make sure its value is parsed so
that userns=auto is parsed and the options for the storage are filled.

Closes: https://github.com/containers/podman/issues/12615

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/test/system/170-run-userns.bats b/test/system/170-run-userns.bats
index 809dd0470..a5be591ef 100644
--- a/test/system/170-run-userns.bats
+++ b/test/system/170-run-userns.bats
@@ -52,3 +52,29 @@ function _require_crun() {
     run_podman 125 run --rm --group-add keep-groups --group-add 457 $IMAGE id
     is "$output" ".*the '--group-add keep-groups' option is not allowed with any other --group-add options" "Check group leaked into container"
 }
+
+@test "podman userns=auto in config file" {
+    skip_if_remote "userns=auto is set on the server"
+
+    if is_rootless; then
+        egrep -q "^$(id -un):" /etc/subuid || skip "no IDs allocated for current user"
+    else
+        egrep -q "^containers:" /etc/subuid || skip "no IDs allocated for user 'containers'"
+    fi
+
+    cat > $PODMAN_TMPDIR/userns_auto.conf <<EOF
+[containers]
+userns="auto"
+EOF
+    # First make sure a user namespace is created
+    CONTAINERS_CONF=$PODMAN_TMPDIR/userns_auto.conf run_podman run -d $IMAGE sleep infinity
+    cid=$output
+
+    run_podman inspect --format '{{.HostConfig.UsernsMode}}' $cid
+    is "$output" "private" "Check that a user namespace was created for the container"
+
+    run_podman rm -t 0 -f $cid
+
+    # Then check that the main user is not mapped into the user namespace
+    CONTAINERS_CONF=$PODMAN_TMPDIR/userns_auto.conf run_podman 0 run --rm $IMAGE awk '{if($2 == "0"){exit 1}}' /proc/self/uid_map /proc/self/gid_map
+}